The electorate which will choose the next PD leader is split into three electoral colleges, all of which have different weights, adding up to 100 per cent.
The first college is the parliamentary party. Thirteen people will be entitled to vote in this college. This will account for 40 per cent of the entire vote.
The second college is made up of the party's 29 local councillors, national executive and trustees, 42 people in all. Their votes are allotted a weighting of 30 per cent, meaning that a candidate who, for example, took half of the 42 votes would be allotted 15 per cent in the overall race.
The third college is the general party membership, which is also allotted a weighting of 30 per cent. In theory there are 3,000 members of the party, but the valid electorate is expected to diminish significantly, as they are required to be active, paid-up members for the last 12 months.
Closing date for nominations is midday next Monday.